During the past several years, there have been many products introduced to allow monitoring of infants and others for reasons of safety. Parents and others are able to monitor subjects who are located in different rooms of a dwelling or in completely different locations. Wired intercom systems that existed more than 60 years ago have been replaced by or supplemented with handy wireless equipment. More recently, communication for monitoring purposes has been supplemented with remote monitoring of bodily functions such as breathing and heart rate. Remote vital sign monitoring of cardiac and other patients by professional organizations has been supplemented with low cost equipment for consumers.